Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Nam’s score on the test is the highest in the class; he _________ hard last night.
 
A.should have studied 
B.may have to study    
C.must have studied  
D.could have studied

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
________you do better work than this, you won't pass the exam
 
A.If   
B.Although  
C.When      
D.Unless

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
If she ________ sick, she would have gone out with me to the party.

A.wasn’t     
B.hadn’t been  
C.hasn’t been
D.weren’t

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
            Speech is one of the most important (55) _________ of communicating. It consists of far more than just making noises. To talk and also to (56) _________ by other people, we have to speak a language, that is,  we have to use combinations of (57)_________ that everyone agrees to stand for a particular object or idea. Communication would be impossible if everyone made up their own language. Learning a language properly is very (58)_________ . The basic (59) _________  of English is not very large, and not only about 2,000 words are needed to speak it quite (60) _________. But the more idea you can (61) _________ the more precise you can be about their exact meaning. Words are the (62)_________  thing we use in communicating what we want to say. The way we (63) _________ the words is  also very important. Our tone of voice can express many emotions and (64) _________  whether we are  pleased or angry, for instance.
(59)_________
A.vocabulary
B.grammar 
C.structure 
D.word

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
            Speech is one of the most important (55) _________ of communicating. It consists of far more than just making noises. To talk and also to (56) _________ by other people, we have to speak a language, that is,  we have to use combinations of (57)_________ that everyone agrees to stand for a particular object or idea. Communication would be impossible if everyone made up their own language. Learning a language properly is very (58)_________ . The basic (59) _________  of English is not very large, and not only about 2,000 words are needed to speak it quite (60) _________. But the more idea you can (61) _________ the more precise you can be about their exact meaning. Words are the (62)_________  thing we use in communicating what we want to say. The way we (63) _________ the words is  also very important. Our tone of voice can express many emotions and (64) _________  whether we are  pleased or angry, for instance.
(58)_________
A.simple
B.important
C.expensive
D.easy

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
            Speech is one of the most important (55) _________ of communicating. It consists of far more than just making noises. To talk and also to (56) _________ by other people, we have to speak a language, that is,  we have to use combinations of (57)_________ that everyone agrees to stand for a particular object or idea. Communication would be impossible if everyone made up their own language. Learning a language properly is very (58)_________ . The basic (59) _________  of English is not very large, and not only about 2,000 words are needed to speak it quite (60) _________. But the more idea you can (61) _________ the more precise you can be about their exact meaning. Words are the (62)_________  thing we use in communicating what we want to say. The way we (63) _________ the words is  also very important. Our tone of voice can express many emotions and (64) _________  whether we are  pleased or angry, for instance.
(57)________
A.systems
B.talks 
C.sounds
D.languages

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
            Speech is one of the most important (55) _________ of communicating. It consists of far more than just making noises. To talk and also to (56) _________ by other people, we have to speak a language, that is,  we have to use combinations of (57)_________ that everyone agrees to stand for a particular object or idea. Communication would be impossible if everyone made up their own language. Learning a language properly is very (58)_________ . The basic (59) _________  of English is not very large, and not only about 2,000 words are needed to speak it quite (60) _________. But the more idea you can (61) _________ the more precise you can be about their exact meaning. Words are the (62)_________  thing we use in communicating what we want to say. The way we (63) _________ the words is  also very important. Our tone of voice can express many emotions and (64) _________  whether we are  pleased or angry, for instance.
(56)________
A.be spoken
B.be examined    
C.be understood 
D.be talked

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
            Speech is one of the most important (55) _________ of communicating. It consists of far more than just making noises. To talk and also to (56) _________ by other people, we have to speak a language, that is,  we have to use combinations of (57)_________ that everyone agrees to stand for a particular object or idea. Communication would be impossible if everyone made up their own language. Learning a language properly is very (58)_________ . The basic (59) _________  of English is not very large, and not only about 2,000 words are needed to speak it quite (60) _________. But the more idea you can (61) _________ the more precise you can be about their exact meaning. Words are the (62)_________  thing we use in communicating what we want to say. The way we (63) _________ the words is  also very important. Our tone of voice can express many emotions and (64) _________  whether we are  pleased or angry, for instance.
(55)_________
A.rules
B.reason
C.ways  
D.tests

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
          An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled - a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of the health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions.
          Many of the more important air pollutants, such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentration of these pollutants was altered by various chemical reactions; they became components in biogeochemical cycles. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil. On a global basis, nature's output of these compounds dwarfs that resulting from human activities.
          However, human production usually occurs in a localized area, such as a city. In such a region, human output may be dominant and may temporarily overload the natural purification scheme of the cycles. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact, the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, has a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.
The word "adversely" in the first paragraph is closest in meaning to  _________ .
A.negatively  
B.admittedly      
C.considerably
D.quickly

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
          An air pollutant is defined as a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled - a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of the health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions.
          Many of the more important air pollutants, such as sulfur oxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentration of these pollutants was altered by various chemical reactions; they became components in biogeochemical cycles. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil. On a global basis, nature's output of these compounds dwarfs that resulting from human activities.
          However, human production usually occurs in a localized area, such as a city. In such a region, human output may be dominant and may temporarily overload the natural purification scheme of the cycles. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentration need not be large for a substance to be a pollutant; in fact, the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, has a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.
For which of the following reasons can natural pollutants play an important role in controlling air pollution?
        
A.They occur in greater quantities than other pollutants.  
B.They function as part of a purification process.  
C.They are less harmful to living beings than other pollutants.
D.They have existed since the Earth developed.